SOS Pipeline: Structure of the [FeFe]-hydrogenase PbHydA from Paraclostridium bifermentans

The [FeFe]-hydrogenase PbHydA from Paraclostridium bifermentans shows both very high reactivity towards H2 production and an oxygen protected inactive conformation, which can be completely reversed to the active state. To understand the molecular basis of this high oxygen tolerance we need to resolve the 3D structure of the enzyme. We were able to produce the enzyme in this oxygen tolerant state at high purity and in high enough yields to begin structural work. As it forms stable tetramers, the overall size (300kDa) is in the target range for SPA analysis. We apply for access to the SOS SPA pipeline based on previous encouraging results during the CryoEM Workshop in May 2023.